Customer service was great but charging me a $163 ...

Customer service was great but charging me a $163 diagnostic fee for a missing bolt that cost's $25 is a little excessive. I understand you need to pay your employees but maybe service charge's should be based off what the issue is and not umbrella everything as one fee. I feel ripped off. I have always been a supporter of GM and will continue to buy cars with your company but I am very unhappy with the price of diagnostics for what was wrong.